综合评价中一种凹性指数型功效函数

目前主流功效函数多为凸性,在处理社会经济数据集中常见的右偏样本时效果难以令人满意。通过系统探讨凸性和凹性功效函数各自的适用特征,指出凹性函数在应用中有其必要性。归纳并使用偏度、区分度、P-P图三种方法作为分布形态的评判标准,比较了常见功效函数对指标原始数据分布形态的调整作用。在分析基础上,提出一种改进的凹性指数功效函数,能有效地处理右偏数据,且相比使用对数预处理的凸性功效函数更具适用性与便利性。     

中国生产性服务业TFP的时空差异与影响因素分析

在利用Malmquist指数法测算2005-2013年中国30个省份生产性服务业的全要素生产率(TFP)的基础上,采用核密度估计法分析了TFP的动态演变,并运用分位数回归方法对中国生产性服务业TFP的影响因素进行了实证分析。研究发现:在考察期内中国生产性服务业TFP总体呈下降态势,技术效率下降是其下降的主要原因;核密度曲线说明中国生产性服务业TFP省际差距扩大,技术效率和技术进步逐渐呈现两极分化的趋势;分位数回归结果表明,工业化水平和人力资本水平对生产性服务业TFP提升具有普遍的促进作用,而信息化水平、对外开放水平、制造业集中度对生产性服务业TFP提高的贡献大小均与地区生产性服务业TFP的水平有关。     

扶贫政策的负外部性及其化解

在脱贫攻坚中,对重点贫困地区的精确瞄准与偏向投入,在一定程度上对非贫困县、非贫困村与非贫困户产生了必然的政策负外部性,表现为县域脱贫结构失衡、村庄帮扶悬崖效应与边缘人群争贫风险。究其原由,在公共政策过程中,竞争性的政策汲取、排他性的政策分配与分割性的政策评价是负外部性的三种发生机理。为此需要建立上下融合减贫机制,探索社区主导发展模式,拓展村民赋权参与空间,通过政策纠正、调适以消解和弥补政策负效应,强化政治决策与分配的正义性。     

Quasi-binomial zero-inflated regression model suitable for variables with bounded support

In recent years, a variety of regression models, including zero-inflated and hurdle versions, have been proposed to explain the case of a dependent variable with respect to exogenous covariates. Apart from the classical Poisson, negative binomial and generalised Poisson distributions, many proposals have appeared in the statistical literature, perhaps in response to the new possibilities offered by advanced software that now enables researchers to implement numerous special functions in a relatively simple way. However, we believe that a significant research gap remains, since very little attention has been paid to the quasi-binomial distribution, which was first proposed over fifty years ago. We believe this distribution might constitute a valid alternative to existing regression models, in situations in which the variable has bounded support. Therefore, in this paper we present a zero-inflated regression model based on the quasi-binomial distribution, taking into account the moments and maximum likelihood estimators, and perform a score test to compare the zero-inflated quasi-binomial distribution with the zero-inflated binomial distribution, and the zero-inflated model with the homogeneous model (the model in which covariates are not considered). This analysis is illustrated with two data sets that are well known in the statistical literature and which contain a large number of zeros.     

A new heavy-tailed distribution defined on the bounded interval: the logit slash distribution and its application

This paper proposes a new heavy-tailed and alternative slash type distribution on a bounded interval via a relation of a slash random variable with respect to the standard logistic function to model the real data set with skewed and high kurtosis which includes the outlier observation. Some basic statistical properties of the newly defined distribution are studied. We derive the maximum likelihood, least-square, and weighted least-square estimations of its parameters. We assess the performance of the estimators of these estimation methods by the simulation study. Moreover, an application to real data demonstrates that the proposed distribution can provide a better fit than well-known bounded distributions in the literature when the skewed data set with high kurtosis contains the outlier observations.     

Inference on a progressive type I interval-censored truncated normal distribution

In this paper, we consider the problem of making statistical inference for a truncated normal distribution under progressive type I interval censoring. We obtain maximum likelihood estimators of unknown parameters using the expectation-maximization algorithm and in sequel, we also compute corresponding midpoint estimates of parameters. Estimation based on the probability plot method is also considered. Asymptotic confidence intervals of unknown parameters are constructed based on the observed Fisher information matrix. We obtain Bayes estimators of parameters with respect to informative and non-informative prior distributions under squared error and linex loss functions. We compute these estimates using the importance sampling procedure. The highest posterior density intervals of unknown parameters are constructed as well. We present a Monte Carlo simulation study to compare the performance of proposed point and interval estimators. Analysis of a real data set is also performed for illustration purposes. Finally, inspection times and optimal censoring plans based on the expected Fisher information matrix are discussed.     

Statistical inference based on generalized Lindley record values

This paper addresses the problems of frequentist and Bayesian estimation for the unknown parameters of generalized Lindley distribution based on lower record values. We first derive the exact explicit expressions for the single and product moments of lower record values, and then use these results to compute the means, variances and covariance between two lower record values. We next obtain the maximum likelihood estimators and associated asymptotic confidence intervals. Furthermore, we obtain Bayes estimators under the assumption of gamma priors on both the shape and the scale parameters of the generalized Lindley distribution, and associated the highest posterior density interval estimates. The Bayesian estimation is studied with respect to both symmetric (squared error) and asymmetric (linear-exponential (LINEX)) loss functions. Finally, we compute Bayesian predictive estimates and predictive interval estimates for the future record values. To illustrate the findings, one real data set is analyzed, and Monte Carlo simulations are performed to compare the performances of the proposed methods of estimation and prediction.     

宁远平话的入声研究

宁远平话保留了入声调类,但是入声的来源复杂,除了中古清声母入声字今读入声外,少数浊声母入声字和某些舒声字在平话中也读入声,通过历时来源和现时分布的考察,可以发现宁远平话的入声演变是从浊声母和送气声母开始的,主要元音是低元音和复元音的入声演变比较快。入声通过连读变调,官话的影响继续演变。     

新冠肺炎疫情下对完善快递末端配送体系建设的思考——以重庆市为例

自新冠肺炎疫情发生以来,快递业为应急救援物资和人民群众日常基本生活物资运输和寄递服务、畅通经济循环、满足民生需要等方面做出了重要贡献,为疫情防控提供了强有力的支撑;但同时也暴露出了一些问题,集中体现在末端配送体系不健全、末端收投不畅等方面。在对电子商务和快递业发展现状进行分析的基础上,对快递末端配送的主要模式和发展趋势进行了论述,结合重庆市的实际情况,分析了其末端配送存在的不足,并从公共服务平台搭建、智能化无接触式配送构建、乡村快递服务网络完善、快递员队伍建设等方面提出了对策建议,以助推重庆经济社会高质量发展。